Yeah Yeah Beebiss II (イェア・イェア・ビービース II) is an action game developed by Rigg'd Games, Bit Ink Studios and Mega Cat Studios, and published by Rigg'd Games. It was also released for Dreamcast, Switch, PC, Evercade and Antstream.

The game has no real predecessor. The title is derived from Yeah Yeah Beebiss I, a title that appeared on the lists of two American mail order services in 1989 without any information. It became one of the greatest unsolved mysteries regarding lost video games. As far as I know, it has still not been fully been solved until this day, whether the game never existed, is a cancelled game or refers to an existing game.

See for example

https://www.youtube.com/watch?v=wR9K-nmc4IA

or

https://www.youtube.com/watch?v=HaYOBQdiHlg

You play one of two characters. Both are Kyonshis (Chinese hopping vampires), which is probably inspired by Rai Rai Kyonshis: Baby Kyonshi no Amida Daibouken. The latter is a Japan-only NES games which is one of the games thought to be Yeah Yeah Beebiss I.

The game is very simple. Each level consists of a single screen and you need to kill off a certain number of enemies within a time limit. You can jump and suck out the lifeforce of things in front of you. There are three types of enemies: an evil mask, dragons and an evil flying eye. The eyes are the only enemies which do not appear randomly. Eyes can only be destroyed temporarily and regenerate after a short time. They also do not count for the number of defeats. Masks mostly just move back and forth. They only sometimes spit out some slime which will hurt you. Dragons extend their tails to strike you. Enemies sometimes leave behind items. A clock will freeze both the timer and all enemies for a few seconds, a heart gives you back health, a potion turns you invincibly for a short time, a "+15" gives you 15 seconds more time, NES cartridges and metroids give you points. If you loose a life, you respawn after a few seconds, you don't have to replay the whole level. If you run out of time, it's game over.

The game can be played in 2-player co-op.